Generally, a radio transmitter and receiver is used for performing a radio transmission and receiving operation, whereby a high frequency signal outputted from a modulator is transmitted to an antenna of the radio transmitter and is transmitted therefrom to a remote radio transmitter and receiver, or the thusly transmitted signal is received through another antenna.
In order to improve a radio transmitting and receiving characteristic of the radio transmitter and receiver, the impedances of the antenna and the radio transmitter and receiver must be accurately matched in accordance with a frequency to be transmitted and received, and a radio loss must be necessarily reduced.
FIG. 1 is a perspective view illustrating a lower portion of a conventional antenna.
As shown therein, there is provided an antenna 1 which is rotatably fixed to one end of a support portion 2, with the antenna 1 and the support portion 2 being separable.
FIG. 2 is a perspective view illustrating a lower portion of another conventional antenna assembly
As shown therein, an antenna 5 is threadably coupled to a support portion 3 by using an engaging member 4, with the antenna 5 and the support portion 2 being separable.
However, in such conventional antennas, since the support portions 2 and 3 for supporting the antennas 1 and 5 are not integral, the antenna assemblies are very difficult to fabricate. In addition, in order to fix the antennas 1 and 5 to the support portions 2 and 3, a hole or a screw portion must be additionally formed in the support portions 2 and 3, for thus fixing the antennas 1 and 5 thereto, so that the constructions thereof become complicated, whereby the fabrication cost is increased.